Improvement In Left Ventricular Contractility Research Articles

Prediction of myocardial contractility after coronary bypass surgery according to preoperative contrast-enhanced magnetic resonance imaging and echocardiography

To establish the criteria for reversibility of myocardial contractility in patients with coronary artery disease (CAD) after coronary artery bypass grafting considering data of cardiac magnetic resonance imaging (MRI) and echocardiography. We studied the results of coronary artery bypass grafting in 186 patients with CAD complicated by reduced left ventricular ejection fraction (<30%). All patients underwent cardiac MRI and echocardiography before surgery. Immediate and long-term results were evaluated according to echocardiography and MRI data. We confirmed the previously established predictors of improvement in left ventricular contractility: diastolic IVST ≥10.5 mm and PWT ≥9.5 mm, score of LV myocardium damage according to MRI with delayed contrast enhancement (p<0.05). Multivariate analysis makes it possible to calculate prognostic index and obtain information about further myocardial contractility after revascularization with an error of 6%. Echocardiography and contrast-enhanced cardiac MRI are valuable to assess morphological and functional state of the left ventricle in patients with ischemic cardiomyopathy and preoperatively determine functional reserve of the myocardium.

Treatment with sacubitril/valsartan and improvement of ventricular-arterial coupling in heart failure with reduced ejection fraction

Abstract Background Treatment with the angiotensin receptor-neprilysin inhibitor sacubitril/valsartan (S/V) in patients with heart failure and reduced ejection fraction (HFrEF) reduces mortality and heart failure (HF) hospitalizations. The specific hemodynamic mechanisms underlying these beneficial effects are currently unclear. Purpose This study aimed to assess the effects of S/V treatment on left ventricular (LV) end-systolic elastance (Ees), effective arterial elastance (Ea), and the ventricular-arterial coupling ratio (Ea/Ees) in patients with HFrEF using non-invasive pressure-volume analysis. Methods 117 patients with symptomatic HF and LVEF &amp;lt;40% in whom treatment with S/V was initiated were enrolled in this multicenter German prospective study. We used transthoracic echocardiography with simultaneous arm-cuff blood pressure measurements for non-invasive pressure-volume loop analyses. Primary endpoints were changes in Ees, Ea, and Ea/Ees ratio after six months of S/V treatment. Results The mean age was 65 (±13) years and 30% were female. In 54.7% of the patients, the etiology of HF was ischemic, and 45.3% was non-ischemic. 58.4% had first HF diagnosis at baseline. 102 patients with complete clinical and echocardiographic data at baseline and after six months of follow-up were analyzed. Among those, 62% were on target dose of S/V. Six months of S/V treatment resulted in a significant increase of Ees (0.66 mmHg/ml, IQR [0.45;0.94] vs. 0.78 mmHg/ml [0.57;1.10], p=0.001) and decrease of Ea (1.76 mmHg/ml [1.48;2.13] vs. 1.62 mmHg/ml [1.36;1.96], p=0.014). Hence, the Ea/Ees ratio significantly improved (2.52 [1.88;4.05] vs. 1.93 [1.50;2.63], p&amp;lt;0.001). In addition, LV volumes and pressure improved significantly with a regression of the LV end-systolic volume (LVESV: 142 ml [115;180] vs. 96 ml [65;124]), end-diastolic volume (LVEDV: 216 ml [179;247] vs. 165 ml [132;200]) and LV end-diastolic pressure (LVEDP: 19.6 mmHg [18.2;22.4] vs. 17.8 mmHg [16.6;19.9]), p&amp;lt;0.001 respectively. The LVEF increased from a median of 33% (27;37) to 43% (36;49), p&amp;lt;0.001. NT-proBNP level decreased from (median) 1771 pg/ml [838;5211] to 724 pg/ml [300;1575] and mean 6-minute walking distance increased from 371m (±125) to 423 m (±122), p&amp;lt;0.001 respectively. The percentage of patients with NYHA class III changed from 25.6% to 5.9%. Conclusion In a 6-months treatment period, initiation of sacubitril/valsartan in patients with heart failure and reduced ejection fraction was associated with reduction of LV volumes, improved LV function, reduction in afterload and fewer heart failure symptoms. These new data indicate that beyond reverse LV remodeling, improvement of LV contractility and ventricular-arterial coupling may contribute to the favorable clinical outcomes on treatment with sacubitril/valsartan in chronic heart failure.

Prognostic value of short-term trajectories of left ventricular ejection fraction in patients with first myocardial infarction and percutaneous coronary intervention

Aim. To assess periprocedural dynamics of left ventricular ejection fraction (LVEF) in patients with first acute myocardial infarction (AMI) and percutaneous coronary intervention (PCI) without heart failure (HF) in the medical history, as well as its prognostic value in the development of cardiovascular complications in the postinfarction period.Materials and methods. A prospective, single-center observational study included 131 patients with first AMI without HF in the past medical history and successful PCI. LVEF was assessed before PCI at admission and before discharge. In patients with reduced baseline LVEF of less than 50%, the criteria for its periprocedural improvement were chosen: 1) LVEF ≥ 50%; 2) ΔLVEF of more than 5%, but EF &lt; 50%. The endpoints were hospitalization for the development of HF and death from cardiovascular disease in combination with the development of HF. The average follow-up period was 2.5 years.Results. At admission, LVEF was &lt; 50% in 74 (56.5%) patients. At discharge, according to the criteria for LVEF improvement, the proportion of patients in this group was 40.5 and 14.9%, respectively. In 44.6% of cases, no increase in LVEF was noted. The predictors of the absence of periprocedural dynamics in LFEF included impaired regional contractility index &gt; 1.94, left ventricular end-systolic volume &gt; 57 ml, left ventricular end-diastolic diameter &gt; 5.1 cm, pulmonary artery systolic pressure &gt;27 mm Hg, NT-proBNP &gt; 530 pg / ml, and E / A ratio &gt; 1.06. During the follow-up period, 28 (21.4%) patients were hospitalized for the development of HF, 33 (25.2%) patients had a combined endpoint. The absence of periprocedural improvement in left ventricular contractility was independently associated with higher odds of hospitalization for HF (relative risk (RR) 3.5; 95% confidence interval (CI) 1.63–7.55; p = 0.001) and the combined endpoint (RR 2.6; 95% CI 1.28–5.48; p = 0.009) in the postinfarction period.Conclusion. In patients with first AMI and left ventricular systolic dysfunction, periprocedural evaluation of LVEF is reasonable to stratify the risk of adverse cardiovascular outcomes.

Effect of vitamin D on myocardial remodeling and inflammatory status in children with congenital heart disease.

Vitamin D insufficiency is a common public health problem that is often unrecognized in children with congenital heart disease, and is not generally evaluated at congenital heart disease (CHD) follow-up. Recent studies have suggested that inadequate vitamin D status may have an adverse effect on cardiovascular health. This study investigates the relationship between vitamin D levels and hemodynamic parameters in children with CHD. Included in the study 40 patients (25 females, 15 males) with CHD, who were evaluated for Ross heart failure score, vitamin D, parathyroid hormone (PTH), calcium, phosphorus, alkaline phosphatase (ALP), whole blood count (WBC) and echocardiographic measurements, and all measurements were repeated in the third month of the therapy. The mean vitamin D level was 16.4 ± 6.6 ug/L before and 27.5 ± 9.9 μg/L in the third month of therapy, while the mean PTH level was 53.3 ± 34.9 pg/mL before and 43.8 ± 21.4 pg/mL in the third month of therapy. The mean WBC was 8084 ± 2324/µL before and 7378±1893/µL in the third month of the therapy, and the mean platelet (PLT) count was 280,897 ± 80,119/µL before and 307,179 ± 60,202/µL in the third month of the therapy. The mean ejection fraction (EF) was 64% ± 7.2% before and 66.7% ± 6.2% in the third month of therapy, while the right ventricle (RV) myocardial performance index (MPI) was 32.1% ± 6.7% before and 28.9% ± 6.5% in the third month of the therapy. IL10 level was increased in four patients in the third month of therapy. A statistically significant decrease in PTH level and WBC, and an increase in PLT number and IL-10 level were detected by the therapy. Furthermore, echocardiographic findings revealed a statistically significant increase in EF and a decrease in RVMPI attributable to the therapy. The decreased levels of PTH, which is a proinflammatory marker, the increases in IL-10, which is an antiinflammatory cytokine, and the decreases in the number of WBC resulting from vitamin D treatment demonstrate the antiinflammatory effects of vitamin D. An improvement in EF means improvement in left ventricular contractility, while a decrease in RV MPI has been shown to improve the systolic and diastolic function of the right ventricle. These results suggest that vitamin D therapy has a positive effect on the heart, and so vitamin D levels should be evaluated during the routine follow-up of congenital heart disease.

Long-term Improvement in Left Ventricular Contractility after the Administration of Empagliflozin in a Patient With Obese Type 2 Diabetes Accompanied by Dilated Cardiomyopathy

Long-term Improvement in Left Ventricular Contractility after the Administration of Empagliflozin in a Patient With Obese Type 2 Diabetes Accompanied by Dilated Cardiomyopathy

SURGICAL TREATMENT OF COMPLEX ARRHYTHMIAS IN PATIENTS WITH NON-ISCHEMIC MITRAL INSUFFICIENCY

Aim: To analyze and improve efficacy of surgical treatment of patients with non-ischemic mitral insufficiency and atrial fibrillation. Materials and methods: The study included 64 patients with degenerative mitral insufficiency complicated by atrial fibrillation who had surgical interventions from 2011 to 2014. Surgical treatment consisted of surgical correction of mitral regurgitation: mitral valve reconstruction (group 1, n = 133) and mechanical prosthesis (group 2, n = 31), as well as left atrium Maze IV procedure in “box lesion” modification with the use of AtriCure bipolar destructor in both groups. Results: No postoperative deaths were registered. After surgery, all patients showed a decrease in all cardiac cavities’ sizes and of pulmonary hypertension, an improvement in left ventricular systolic function assessed by transthoracic echocardiography. During follow-up of up to 14 months’ duration, sinus rhythm was maintained in 56 (86%) of patients, whereas 9 patients had recurrent atrial fibrillation resistant to medications and electrical cardioversion. Patients, who had undergone valve preserving correction of mitral insufficiency and left atrium Maze IV procedure, had the best results as to contractility of left ventricle (7.86%), reduction of cardiac cavities’ size (end-diastolic dimension – 11.05%, end-systolic dimension – 15.15%, right atrium – 15.19%), especially that of left atrium (19.03%), reduction of pulmonary hypertension (27.75%) and significant improvement in quality of life (7 points) assessed by Minnesota Living with Heart Failure Questionnaire. Conclusion: Plastic correction of mitral insufficiency with atrial fibrillation combined with Maze IV procedure gives the highest improvement of left ventricular contractility and diminishing of cavities compared to mitral valve replacement with mechanical prosthesis in combination with Maze IV procedure.

Effects of adaptive servo-ventilation therapy on cardiac function and remodeling in patients with chronic heart failure (SAVIOR-C): study protocol for a randomized controlled trial.

BackgroundAdaptive servo-ventilation (ASV) therapy, which is a form of noninvasive positive pressure ventilation therapy and uses an innovative ventilator that has simple operability and provides good patient adherence, potentially has therapeutic benefits—suppression of the deterioration and progression of chronic heart failure (CHF) and a reduction in the number of repeated hospitalizations. Therefore, ASV therapy draws attention as a novel, noninvasive nonpharmacotherapy for patients with CHF owing to its hemodynamics-improving effect, and it is currently being accepted in real-world clinical settings in Japan. However, clinical evidence sufficient for treatment recommendation is lacking because a multicenter, randomized, controlled study of ASV therapy has never been conducted.Methods/DesignThe present study is a confirmatory, prospective, multicenter, collaborative, open-label, blinded-endpoint, parallel-group, randomized, controlled study. At 40 medical institutions in Japan, 200 Japanese outpatients with mild to severe CHF (age: ≥ 20 years; New York Heart Association classification: greater than or equal to class II) will be randomly assigned to either of the following two study groups: the ASV group, in which 100 outpatients undergo guideline-directed medical therapy and ASV therapy for 24 weeks; and the control group, in which 100 outpatients undergo only guideline-directed medical therapy for 24 weeks. The objective of the present study is to confirm whether the ASV group is superior to the control group concerning the improvement of left ventricular contractility and remodeling, both assessed by two-dimensional echocardiography. Furthermore, the present study will also secondarily examine the effects of ASV therapy on the prognosis and quality of life of patients with CHF.DiscussionASV therapy using the device has the potential to provide therapeutic benefits based on its simple operability and good patient adherence and possesses the potential to improve left ventricular contractility and remodeling. Therefore, the present study is expected to afford more solid scientific evidence regarding ASV therapy as a novel, noninvasive, nonpharmacological, in-home, long-term ventilation therapy for patients with mild to severe CHF.Trial registrationUMIN identifier: UMIN000006549, registered on 17 October, 2011.Electronic supplementary materialThe online version of this article (doi:10.1186/s13063-014-0530-z) contains supplementary material, which is available to authorized users.

Abstract 062: Mitoubiquinone Decreases Reactive Oxygen Species Production and Improves Cardiac Efficiency in Chronic Volume Overload

Background: The hemodynamic stress of left ventricular (LV) volume overload (VO) produces LV dysfunction accompanied by mitochondrial and cytoskeletal disruption in cardiomyocytes. Because mitochondria are both a source and target of reactive oxygen species (ROS), we hypothesize myocyte damage and LV dysfunction are mediated by mitochondrially produced ROS and can be attenuated by the mitochondrially targeted antioxidant, mitoubiquinone (MitoQ). Methods: Aortocaval fistula (ACF) was induced for 8 weeks in adult rats ± MitoQ. Echocardiography and high-fidelity LV pressure catheter recordings were used to study the LV end-systolic pressure-volume relationship and cardiac efficiency. Isolated cardiomyocytes were loaded with Carboxy-H2DFFDA (CM-DCF) and tetramethylrhodamine (TMRM) to measure mitochondrial ROS production and membrane potential. Results: Isolated cardiomyocyte studies demonstrated increased ROS production and decreased mitochondrial membrane potential in VO animals, both of which were attenuated with MitoQ. Treatment with MitoQ demonstrated a strong trend toward improvement in LV contractility, as cardiac efficiency improved significantly in MitoQ-treated VO animals. Untreated VO animals exhibited mitochondrial swelling and myofibrillar disruption that was prevented by MitoQ. Conclusion: These studies suggest an early interplay between mitochondrial-derived ROS production and cardiac ultrastructure and function.

Successful surgical repair of a chronic left ventricular pseudoaneurysm

ENWEndNote BIBJabRef, Mendeley RISPapers, Reference Manager, RefWorks, Zotero AMA Wdowiak-Okrojek K, Lipiec P, Szewczyk M, Lubiński A, D. Kasprzak J. Case reportsSuccessful surgical repair of a chronic left ventricular pseudoaneurysm. Kardiochirurgia i Torakochirurgia Polska/Polish Journal of Thoracic and Cardiovascular Surgery. 2013;10(3):279-282. doi:10.5114/kitp.2013.38103. APA Wdowiak-Okrojek, K., Lipiec, P., Szewczyk, M., Lubiński, A., & D. Kasprzak, J. (2013). Case reportsSuccessful surgical repair of a chronic left ventricular pseudoaneurysm. Kardiochirurgia i Torakochirurgia Polska/Polish Journal of Thoracic and Cardiovascular Surgery, 10(3), 279-282. https://doi.org/10.5114/kitp.2013.38103 Chicago Wdowiak-Okrojek, Katarzyna, Piotr Lipiec, Monika Szewczyk, Andrzej Lubiński, and Jarosław D. Kasprzak. 2013. "Case reportsSuccessful surgical repair of a chronic left ventricular pseudoaneurysm". Kardiochirurgia i Torakochirurgia Polska/Polish Journal of Thoracic and Cardiovascular Surgery 10 (3): 279-282. doi:10.5114/kitp.2013.38103. Harvard Wdowiak-Okrojek, K., Lipiec, P., Szewczyk, M., Lubiński, A., and D. Kasprzak, J. (2013). Case reportsSuccessful surgical repair of a chronic left ventricular pseudoaneurysm. Kardiochirurgia i Torakochirurgia Polska/Polish Journal of Thoracic and Cardiovascular Surgery, 10(3), pp.279-282. https://doi.org/10.5114/kitp.2013.38103 MLA Wdowiak-Okrojek, Katarzyna et al. "Case reportsSuccessful surgical repair of a chronic left ventricular pseudoaneurysm." Kardiochirurgia i Torakochirurgia Polska/Polish Journal of Thoracic and Cardiovascular Surgery, vol. 10, no. 3, 2013, pp. 279-282. doi:10.5114/kitp.2013.38103. Vancouver Wdowiak-Okrojek K, Lipiec P, Szewczyk M, Lubiński A, D. Kasprzak J. Case reportsSuccessful surgical repair of a chronic left ventricular pseudoaneurysm. Kardiochirurgia i Torakochirurgia Polska/Polish Journal of Thoracic and Cardiovascular Surgery. 2013;10(3):279-282. doi:10.5114/kitp.2013.38103.

Four-Dimensional Speckle Tracking for Assessing Improvement in Left Ventricular Contractility After Coronary Angioplasty

The objective of the study was to identify and quantify the potential improvement of left ventricular contractility after percutaneous transluminal coronary angioplasty (PTCA) using 4-dimensional (4D) speckle tracking echocardiography (4D STE). We investigated 41 patients with coronary disease by 4D STE pre- and 24 hours postcoronarography with (n = 18) or without (n = 23) PTCA. The 4D STE visualizes in real time the myocardium strain on 2- and 4-chamber apical views and on 3 transverse views of the left ventricle. Average and total strain of the left ventricle were measured. Of the 18 PTCA patients, 15 showed significant increase in left ventricle mean (+15 ± 6) and total strain (240 ± 100), which corresponded to an increase of 93% ± 55% from precoronarography, whereas the remainder showed no change. The total strain corresponded to 33% ± 10% (before PTCA) and 59% ± 11% (post PTCA) of the estimated normal strain for each patient. Strain improved in 70% of the segment downstream from the stent, and there was a negative correlation between the amplitude of the mean and total strain improvements after 24 hours and the mean and total strain values before PTCA. In the non-PTCA group, 21 of the 23 patients showed no changes in strain, whereas 2 showed improvement. The 4D STE showed significant improvements in left ventricular contractility in more than 70% of the areas downstream from the PTCA segment. This corresponded to an increase in the initial contractility by approximately 93% ± 55%; however, the myocardium contractility remained approximately 59% of normal level. No changes were seen in patients without PTCA.

New Insights into Mechanisms of Action of Carvedilol Treatment in Chronic Heart Failure Patients—A Matter of Time for Contractility

BackgroundIt is unclear whether improvement in left ventricular (LV) ejection fraction (LVEF) following treatment with a combined α1,β1,β2-blockade can be attributed to improvement in LV contractility, to a reduction in afterload, and/or to improvements in LV remodeling and chamber size. We aimed to examine whether the observed improvement in LVEF following carvedilol treatment is due to changes in intrinsic myocardial contractility beyond changes in LV chamber size or loading conditions. Methods and ResultsIn 49 consecutive patients with chronic heart failure (HF), LVEF ≤35%, NYHA functional class II–IV, on angiotensin-converting enzyme inhibitors but not on ß-blockers, LV contractile performance and remodeling were assessed by comprehensive echocardiography at baseline and after 3 and 6 months of treatment with carvedilol. Carvedilol treatment resulted in significant improvements in LVEF, shortening fraction, and velocity of circumferential shortening (VCFc). There were no significant changes in the mean arterial blood pressure or systemic vascular resistance index; but LV end-systolic wall stress (LVESS), effective arterial elastance, ventriculoarterial coupling, and LV end-diastolic and end-systolic dimensions and volumes were significantly reduced. Estimated end-systolic elastance, VCFc-to-LVESS ratio, and pulsatile arterial compliance significantly improved after 6 months of treatment with carvedilol. The slope of the VCFc relationship to LVESS worsened from 0 to 3 months, but significantly improved from 3 to 6 months. ConclusionsDespite an initial transient negative inotropic effect from 0 to 3 months, carvedilol treatment was associated with a positive inotropic effect with significant improvement in load-independent indexes of myocardial contractility beyond what can be attributed to changes in LV chamber size and load after 3 months. There were no changes in systemic vascular resistance with carvedilol treatment; however, improvement in pulsatile arterial compliance and ventriculoarterial coupling suggested enhanced cardiac mechanoenergetic performance along with improved systemic arterial compliance.

Abstract 18051: High Prevalence of Active Myocarditis in Patients with Takotsubo Cardiomyopathy: A Magnetic Resonance-endomyocardial Biopsy Study

Background: Tako-tsubo cardiomyopathy (TTC) was recently classified as a cardiomyopathy with distinct clinical and angiographic features, but mechanisms of cardiac dysfunction and histological substrate are still largely unclear. We evaluated cardiac magnetic resonance (CMR) and endomyocardial biopsy (EMB) findings in patients with TTC. Methods: Twenty consecutive patients (19 F, 58±12 years) with clinical and angiographic features of TTC underwent CMR with edema (STIR images) and delayed enhancement (DE) studies. Of these, 15 patients also underwent EMB. Myocardial samples obtained from apical akinetic left ventricular segments were processed for histology, immunohistochemistry and polymerase chain reaction (PCR) for cardiotropic viruses. Results: All patients presented acute chest pain with ST-segment elevation in anterior leads and evidence of myocardial necrosis. Symptoms were precipitated by emotional stress in 12 (60%) cases. At CMR DE was observed in 11 patients (55%) in all cases with a subepicardial or midventricular pattern; edema was observed in 10 (50%) patients, associated with DE in 8 cases. Neither DE nor edema was observed in 7 patients. In 11 patients (73%) EMB showed an active lymphocytic myocarditis with evidence of activated T lymphocytes. In 4 patients (27%) contraction band necrosis was observed. PCR identified parvovirus B19 viral genome in 3 patients with myocarditis. Among patients with a histological diagnosis of myocarditis CMR showed DE in 10 and edema in 8 cases. One patient with myocarditis had neither DE nor edema at CMR. Patients with contraction-band necrosis showed no DE or edema at CMR. Three myocarditis virus-negative patients failing to recovery after 6 weeks from clinical presentation, received prednisone and azathioprine for 8 weeks with significant improvement of left ventricular contractility. Conclusions: Acute myocarditis represents a frequent substrate of TTC. CMR may help to identify myocardial inflammation in TTC patients. Immunohistochemical and virological diagnosis through EMB may affect both treatment and prognosis. Further studies are needed to clarify the prevalence of acute myocarditis among TTC patients and the possible association between emotional stress and viral infection.

Metabolic and Cardiovascular Effects of Ghrelin

Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor, is synthesized as a preprohormone and then proteolytically processed to yield a 28-amino acid peptide. This peptide was originally reported to induce growth hormone release; large evidence, however, has indicated many other physiological activities of ghrelin, including regulation of food intake and energy balance, as well as of lipid and glucose metabolism. Ghrelin receptors have been detected in the hypothalamus and the pituitary, but also in the cardiovascular system, where ghrelin exerts beneficial hemodynamic activities. Ghrelin administration acutely improves endothelial dysfunction by increasing nitric oxide bioavailability and normalizes the altered balance between endothelin-1 and nitric oxide within the vasculature of patients with metabolic syndrome. Other cardiovascular effects of ghrelin include improvement of left ventricular contractility and cardiac output, as well as reduction of arterial pressure and systemic vascular resistance. In addition, antinflammatory and antiapoptotic actions of ghrelin have been reported both in vivo and in vitro. This review summarizes the most recent findings on the metabolic and cardiovascular effects of ghrelin through GH-dependent and -independent mechanisms and the possible role of ghrelin as a therapeutic molecule for treating cardiovascular diseases.

Effects of Surgical Ventricular Restoration on Left Ventricular Contractility Assessed by a Novel Contractility Index in Patients With Ischemic Cardiomyopathy

A pressure-normalized left ventricular (LV) wall stress (dsigma*/dt(max)) was recently reported as a load-independent index of LV contractility. We hypothesized that this novel contractility index might demonstrate improvement in LV contractile function after surgical ventricular restoration (SVR) using magnetic resonance imaging. A retrospective analysis of magnetic resonance imaging data of 40 patients with ischemic cardiomyopathy who had undergone coronary artery bypass grafting with SVR was performed. LV volumes, ejection fraction, global systolic and diastolic sphericity, and dsigma*/dt(max) were calculated. After SVR, a decrease was found in end-diastolic and end-systolic volume indexes, whereas LV ejection fraction increased from 26% +/- 7% to 31% +/- 10% (p <0.001). LV mass index and peak normalized wall stress were decreased, whereas the sphericity index (SI) at end-diastole increased, indicating that the left ventricle became more spherical after SVR. LV contractility index dsigma*/dt(max) improvement (from 2.69 +/- 0.74 to 3.23 +/- 0.73 s(-1), p <0.001) was associated with shape change as evaluated by the difference in SI between diastole and systole (r = 0.32, p <0.001, preoperative; r = 0.23, p <0.001, postoperative), but not with baseline LV SI. In conclusion, SVR excludes akinetic LV segments and decreases LV wall stress. Despite an increase in sphericity, LV contractility, as determined by dsigma*/dt(max), actually improves. A complex interaction of LV maximal flow rate and LV mass may explain the improvement in LV contractility after SVR. Because dsigma*/dt(max) can be estimated from simple noninvasive measurements, this underscores its clinical utility for assessment of contractile function with therapeutic intervention.

Transitional QRS Morphology during CRT Timing Optimization Is Associated with the Largest Improvement in Myocardial Performance Index

Background: Optimization of CRT timing may result in an improvement in cardiac function and long-term clinical outcome. Previous studies have suggested that the maximal improvement in left-ventricular contractility is achieved when fusion between electrical excitation wavefronts originating from the left- (LV) and right-ventricular (RV) pacing sites is observed. We investigated the relationship between QRS morphology in surface ECG and echocardiographic indices of cardiac function upon changes in CRT timing.

NT‐proBNP response to dobutamine stress echocardiography predicts left ventricular contractile reserve in dilated cardiomyopathy

Brain natriuretic peptide (BNP) and left ventricular (LV) inotropic reserve are major prognostic indexes in heart failure (HF). To investigate the relationship between N-terminal-proBNP (NT-proBNP) changes in response to dobutamine stress echocardiography (DSE) and the LV inotropic reserve, in HF patients with dilated cardiomyopathy (DC). We studied 41 patients with DC, LVEF 31.6+/-7.7%, NYHA class II-III and 15 controls. Plasma NT-proBNP levels were measured before and 60 min after three 5-min stages of dobutamine (5 to 15 microg/kg/min). Based on NT-proBNP changes in response to dobutamine, patients were categorized into two groups: In Group A circulating NT-proBNP levels fell (-16.6+/-7.8%), and in Group B they increased (8.4+/-9.1%). Group A had a marked improvement in WMSI compared to Group B (32.1+/-9.7% vs. 18.8+/-15.9%, p<0.001). Multivariate analysis showed that NT-proBNP changes were an independent predictor of LV inotropic reserve (b= -0.55, p<0.001). A reduction of 21.3% in plasma NT-proBNP levels in response to dobutamine predicted an improvement in WMSI of >25% with a sensitivity of 100% and a specificity of 92.3%. NT-proBNP changes in response to dobutamine reflect improvement in LV contractility and constitute an independent predictor of LV inotropic reserve in patients with DC.

Muscle Metaboreflex Control of Coronary Blood Flow and Ventricular Contractility During Dynamic Exercise

Muscle metaboreflex activation (MMA) during dynamic exercise induces a substantial increase in cardiac work and oxygen demand via a significant increase in heart rate, ventricular contractility and afterload. This increase in cardiac work should lead to coronary metabolic vasodilation. However, in this situation, little if any coronary vasodilation is observed. It is unclear if this lack of coronary vasodilation, which occurs as a result of increased coronary sympathetic stimulation due to MMA, suppresses any further increases in left ventricular contractility (LVC). The purpose of this study was to determine if this lack of coronary vasodilation leads to a buffered increase in LVC. Using chronically instrumented, conscious dogs we measured arterial pressure, cardiac output (CO), circumflex blood flow (CxBF), and calculated coronary vascular conductance (CVC), maximal derivative of ventricular pressure (dp/dt), and preload recruitable stroke work (PRSW) at rest and during mild exercise (2mph) before and after MMA. Experiments were repeated after alpha-1 adrenergic blockade (prazosin ∼50 ìg/kg). During prazosin we observed significantly greater increases in CVC, CxBF, CO, dP/dt, and PRSW, with MMA, over that of the control condition. We conclude that the lack of coronary vasodilation limits further improvement in LVC. NIH HL 55473

Beneficial effects of endoventricular circular patch plasty in patients with left ventricular systolic dysfunction and left ventricular dyskinetic or akinetic apical segment

Available data on the efficiency of endoventricular circular patch plasty (EVCPP) especially from Asian Indians are limited. The objective of the present investigation was to evaluate the efficacy of endoventricular circular patch plasty along with coronary artery bypass grafting (CABG). Patients having ischemic left ventricular (LV) systolic dysfunction [LV ejection fraction (LVEF)≤25%] with left ventricular dyskinetic or akinetic apical segement [as depicted by two dimensional (2D) echocardiography] were enrolled in the study. They were evaluated for 2D echocardiography and color Doppler parameters as well as functional capacity before surgery and after one, three and six months of surgery. 39 patients (35 males; average age 59 years) were enrolled in the study. There was significant (P<0.05) increase in LV contractility measured in terms of LVEF with absolute rise of 8–14 digits from presurgery levels during time course of the study. EVCPP performed in addition to CABG produced significant reduction in LV end diastolic diameter (5–5.5 mm) and LV end systolic diameter (4.5–8.5 mm) at short-and intermediate-term following surgery. EVCPP plus CABG also produced significant improvement in functional capacity as a significant decrease in New York Heart Association class for heart failure was observed at all three stages of follow-up after surgery. EVCPP carried out along with CABG produces significant improvement in LV contractility, in reverting LV remodeling and functional status in Indian patients with LV systolic dysfunction and LV dyskinetic or akinetic apical segment at shor-term as well as intermediate-term following surgery.

Cardioprotection from ischemia‐reperfusion injury due to Ras‐GTPase inhibition is attenuated by glibenclamide in the globally ischemic heart

The present study was designed to see if acute local inhibition of Ras-GTPase before or after ischemia (during perfusion) would produce protection against ischemia and reperfusion (I/R)-induced cardiac dysfunction. The effect of glibenclamide, an inhibitor of cardiac mitochondrial ATP-sensitive potassium (mitoK(ATP)) channels, on Ras-GTPase-mediated cardioprotection was also studied. A 40 min episode of global ischemia followed by a 30 min reperfusion in perfused rat hearts produced significantly impaired cardiac function, measured as left ventricular developed pressure (P(max)) and left ventricular end-diastolic pressure (LVEDP). Perfusion with Ras-GTPase inhibitor FPT III before I/R [FPT(pre)], significantly enhanced cardiac recovery in terms of left ventricular contractility. P(max) was significantly higher at the end of 30 min reperfusion in FPT(pre)-treated hearts compared to pre-conditioned hearts. However, the degree of improvement in left ventricular contractility was significantly less when FPT III was given only after ischemia during reperfusion [FPT(post)]. Combination treatment with FPT III and glibenclamide before I/R resulted in significant reduction of FPT III-mediated cardioprotection. These data suggest that activation of Ras-GTPase signaling pathways during ischemia are critical in the development of left ventricular dysfunction and that opening of mitoK(ATP) channels, at least in part, contributes to cardioprotection produced by Ras-GTPase inhibition.

Autologous transplantation of CD133+ BM-derived stem cells as a therapeutic option for dilatative cardiomyopathy

We report the case of a 58-year-old man with end-stage non-ischemic cardiomyopathy. Baseline transthoracic echocardiography (TTE) and cardiac magnetic resonance (cMRI) revealed a markedly depressed left ventricle systolic function. He underwent autologous CD133+ BM-derived cell transplantation through a minimally invasive approach. During surgery 19 x 10(6) BM-derived stem cells were injected by the transepimyocardial route. Six months after the operation TTE and cMRI showed a clear improvement in left ventricular contractility.